Sleeve-valve internal-combustion engine



H. R. RICARDO June 18, 1929..1 I

SLEEVEVALVE INTERNAL COMBUSTIONA ENGIE Filed July l2o, 192e Patented June 18, A19.29.

UNITED .STATES PATENT o'FFicE.

HARRY RALIEH RICAZRD, F LONDON, ENGLAND. v

SLEEVE-VALVE INTERNAL-COMBUSTION IilNi'IN'IEl.y

Application filed July 20, 1928, Serial No. 294,267, and in Great Britain August 18, 1927.

This invention relates to four-cycle internal combustion engines of the type in which the-inlet and exhaust ports are controlled by a single sleeve valve having a combined oscillating and reciprocating motion, and'has for its object to render the combustionin this type 'of engine more efficient.

In engines ofthis type the cylinder charge,

I during combustion, is in rapid rotation about l0 the cylinder axis owing to the lateral opening of the inlet ports which imparts to the entering charge a tangential motion. -This rotation or swirl is of very little value for distributing the fiame and if excessive, it gives trouble through excessive heat loss and centrifugal separation of the liquid fuel in the charge.

According to the present invention, the combustion chamber is so formed as to impede the swirl, and thus slow it down, during the compression stroke, to the desired figure. The most convenient method of reta'rding the swirl, is to form the combustionchamber so vthatthe whole, or 'a substantial part thereof, has a non-circular section about the cylinderl axis. lVhere, as is common, the combustion chamber is of. conical, frustro-conical, or cylindrical shape, and is carried mainly within the cylinder head pot, it may be formed with a cross-section lobed (e. g. clover-leaf?) or polygonal. In another type of coinbustion `chamber, which is carried mainly between tlie head and the piston, being bounded at the sides by the sleeve walls, either the cylinder head or the piston crown may be of sloping, stepped or other irregular form, adapted to reduce the swirl. In certain cases it may be desirable to use both methods in combination, as for example the combination With a lobcd cylinder head with' a stepped piston.

The step or steps on the piston or head should be otherwise than circular or concentric with the cylinder axis7 for example a transversely extending projccting'part may be provided, the ends of this projection stopping short of the circumferential periphery of the piston if the projection `is mounted thereon, or being paired oli' so as to leave clearance for the flow of gas from or to the port-s. If mounted on the cylinder head, l there may be for example two transverseprojections spaced apart and having a transverse recess between them.

Various constructional forms may be adopted in accordance with this invention but two alternativearrangements according to this invention are illustrated by Way of example in the accompanying drawings, in

which Figure 1 is a sectional side elevation in 'a plane at lright angles to the crankshaft axis of one construction of internal combustion engine according to this invention,

Figure 2 is'a plan view of the-piston ein' ployed vin the construction illustrated in Figure l,

Figure 3 1s a sectional side elevation of the upper partof the cylinder vandthe cylinder head of an alternative form of internal coin-A bution engine accordinglto thisinvention, an r F igure'Li is a section through the cylinder head on the line 4-4 of Figure 3.v

In the construction .illustrated in Figures l and 2, the engine comprises a crank case A in which is-,rnounted a crankshaft A1. Supported on the crank case A is a Water-cooled cylinder B within which is mounted a sleeve valve C. The sleeve valve C which controls inlet and exhaust ports B1, B2 in the cylinder lwall has a. combined oscillating' and reciprocating motion imparted thereto in known Vmanner by a crank pin D1 carried by a lay shaft indicated at D which'is driven through suitable gearing from the crankshaft A1.

The outer end of the cylinder B is closed which extends into the upperend of the sleeve C and carries a sparking plug F.

As so far describedI theengline is of known form.

Reciprocating within the sleeve C and operatively connected to the crankshaft A1 by a connecting rod G is a piston H which according to the constructional form of the invention now being described'is provided with a radial rib or projection H1 on its face which -by a plug-like Waterecooled cylinder head E tends toinipede the rotational motion of the cliarge about the cylinder axis. This rib conin Figures l and 2. In the construction il:

lustrated in Figures 3 and 4, however, the combustion chamber E1 is formed mainly in cal form as shown in Figure 3 While theface of the piston H8 is Substantially flat or slightly concave as shown. Inthis construction in order t'o impede excessive rotational motion of the charge about the combustion chamber axis,the combustion chamber is of iion-circular' form in cross-section and .in the conconstructions described above are given by Y Way of example only and that the form of the combustion chamber may varyAA considerably Without departing from vthe present invention. I

Vhat l claim as my invention and desirew (j.

secure'by Letters Patent is 1. An internal combustion engineincludf ing in combination a cylinder, a sleeve valvei disposed Within the cylinder and controlling inlet and exhaust ports in the cylinder vvall,

means for imparting to the sleeve valve a" combined oscillating and reciprocating motion of which both components combine in the control` of the' ports by the sleeve valve a plug-like cylinder head E2 and considered ,in sectional elevation is of substantially coni;

ciprocating motion of which both cbmponentscombi'ne in thevcontrol of the ports by thev sleeve valve andtend to cause the infiowing gaseous charge to rotate in the cylinder about the cylinder axis, a-.piston recip- "rocating Within the sleeve valve,.and a combustion chamber having a partWith a formation other than circular Whicliwill impede rotationfal motion of the charge in the combustion chamber.

4. Anf internal Vcombustion engine including in combination a cylinder, a sleeve valve disposed Within the cylinder and controlling inlet and exhaust ports in the cylinder Wall,v

means for imparting to thefsleeve valve a` combined oscillating and reciprocating motion both components of such motion conibinand tend to cause the inflo'vving gaseouscharge to rotate in the cylinder about the cylinder axis, a piston reciprocating Within t ie sleeve valve, and la `combustion chamber a part of which constitutesan obstruction to'- rotational motion of the charge about the ycylinder axis.

2. An internal combustion engine including in combination' .a cylinder, a sleeve valve disposed-,Within'the cylinder and controlling inlet and exhaust ports in the cylinder Wall, means for imparting to the sleeve valv'e a combined oscillating and reciprocating mo-`v tion of Which 'both components conbi'ne ,in

charge to rotate inthe cylinder about the cylinder axis, a piston reciprocating Withiny the sleeve valve, and a combustion chamber bounded by the sleeve valve wall, thecylinder head andthe pistoni'a'ceg'and having a part of such boundary formed to constitute anob.- struction to rotational motion of the charge about the combustion chamber axis.

3. An internal combustion engineiincludving in combination a cylinder, a -sleeve valve disposed Within the cylinder and ing in the control ofi the ports by the sleeve va ve, and a piston reciprocating Within the L sleeve valve, the formation o'at least one Wall of the combustion chamber"\bounded by the piston, sleeve and cylinderhead, being such asto impede rotational mtion ofthe charge about the combustion chamber axis. i

5. An internalcombustion engine including in combination a cylinder, a sleeve valve disposed Within' the cyilinder and controlling inlet and exhaust ports inthe cylinder Wall,

imeans for imparting to the. sleeve valve a combined oscillating' and reciprocating mo-y tion both components of such motion combininfr in the control of the ports, a plug-like cy inder head1-extending into the outer lend of the sleeve and containing a combustion chamber atleast one part of which is of noncircularcross-sectionin a plane at` right angles to the cylinder axis, and valpisten reciprocating Within thesleeve valve.

6. An internal combustionengine ineluding in combination a cylinder, a sleeve valve disposed Within the cylinder and controlling tion'both components of which motion combine te control vthe ports, a plug-like cyliny, inlet vand exhaust ports inthe cylinder wall, .the control of the ports by the sleeve valve and tend to Acause the inilovving gaseous der head extendingl into' the outer enl'ofthe i sleeve and containing a combustion chamber the cross-section of Which in a plane at right angles to the cylinder axis 1s of lobed .formation, and a piston reciprocating Within-the sleeve valve.

In testimony whereot1 have vsigned my name to this specifi-cation. 1

HARRY RALPH` RICARDO. 

